JPH04302782A - Method of checking the flow of crude oil from oil well and method of changing flow passage therefor - Google Patents

Abstract

PURPOSE:To achieve a safe and reliable crude-oil passage halt, with a simplified structure, at the time of, for example, a fire of an oil well, by forming an opening in the casings for a tubing constituting a crude-oil flow passage in the oil well, and reducing the caliber of the tubing, thereby blocking the tubing interior. CONSTITUTION:The oil well is composed of a Christmas-tree 1 located on the ground, an oil draw-out tube or tubing 2 constituting a crude oil flow passage, and a plurality of casings 3 located surrounding the tubing 2. When stopping the flow of a crude oil in case the oil well is fired, the wall of the casing 3 is first made open by cutting to thereby form an opening through which access is made to the wall of the tubing 2. A detonating primer 4, a booster drug 5 and an explosive compound 6 for example are mounted to the casing 3 to form the opening. Next, the tube wall of the tubing 2 is pressed toward a center thereof to reduce the caliber thereof and blocking the tubing 2. For instance, an explosion causing wire 8 is wound around a shock-absorbing member 10 cladding the tubing 2 to contract the tubing 2 by explosion.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is useful in emergency cases where the spillage of crude oil from an oil well cannot be controlled by an oil well control device installed on the ground, such as a Christmas tree control valve, etc., such as a fire in an oil well. This invention relates to a method for stopping the flow of crude oil in an oil well and a method for changing the flow path of crude oil in an oil well.

0002

BACKGROUND OF THE INVENTION Conventionally, methods for extinguishing oil well fires include blowing out the flames and stopping crude oil from blowing out. The method of blowing out flames is to use explosives to detonate a burning oil well and use the resulting blast to blow away the flames. There are two methods to stop the oil from blowing out: one is to inject muddy water into the burning oil well to block the tubing, and the other is to drill a diagonal hole several thousand meters into the part of the well that has been pushed into the oil layer. There is a method of plugging the tubing by pouring cement into the tubing of the oil well using the hole.

0003

[Problems to be Solved by the Invention] However, with the method of blowing out the flames, it is difficult to blow out the flames if the fire area is large, and if the temperature of the crude oil has increased due to the fire, it is difficult to blow out the flames. However, there was a problem that the fuel could ignite again and cause another fire. In addition, the method of injecting muddy water cannot be adopted if the fire is strong because it is impossible to get close to the oil well and the muddy water cannot be injected. The method of using diagonal holes requires drilling several thousand meters of diagonal holes, which is equivalent to building another oil well, and has the problem of being extremely expensive. Oil well fires not only waste crude oil but also pollute the environment by releasing harmful substances into the atmosphere.
It is necessary to extinguish the fire as soon as possible, and when extinguishing the fire,
A simple and effective fire extinguishing method is desired. In view of the above-mentioned problems, the present invention aims to safely and at minimum cost reduce the amount of crude oil in an oil well in case of an emergency during the operation of an oil well, for example, in the case of a fire in an oil well, regardless of the size of the fire in the oil well and the strength of the fire. The objective is to provide a method for stopping the flow and for changing the flow path of crude oil in an oil well.

0004

[Means for Solving the Problems] As a result of intensive research to solve the problems of conventional methods, the present inventors have discovered that the flow of crude oil in an oil well can be stopped by a specific method according to the present invention. It has also been found that the flow path of crude oil in an oil well can be altered by certain methods according to the invention. The method of stopping the flow of crude oil in an oil well according to the present invention is used to extinguish a fire in an oil well by stopping the flow of crude oil itself, and the method of changing the flow path of crude oil in an oil well according to the present invention is used to suppress the flow path of crude oil. The oil well can be regenerated by changing it.

[0005] A method of stopping the flow of crude oil in an oil well according to the first invention is to cut the wall of the casing that surrounds the tubing that forms the crude oil flow path of the oil well on the outside, and to cut the wall of the tubing. A method for stopping the flow of crude oil in an oil well, comprising: providing an accessible opening; and then pressing the wall of the tubing toward the center of the tubing to reduce the diameter of the tubing and occlude the tubing. be. In carrying out the invention, gunpowder is preferably used to incise the wall of the casing and press the tubing. A method for stopping the flow of crude oil in an oil well according to a second aspect of the invention is to cut a wall of a casing that surrounds the tubing that forms the crude oil flow path of the oil well on the outside to open an opening that allows access to the wall of the tubing. , then an opening is provided by cutting the tube wall of the tube without allowing the fluid flowing inside the tube to flow outside, and an inflatable bag is inserted into the tube through the opening. an inflatable bag insertion device that can be inflated is attached to the tube wall of the tubing, an opening is provided in the tube wall of the tubing by the inflatable bag insertion device, and the inflatable bag is inserted into the tube wall of the tubing. This is a method for stopping the flow of crude oil in an oil well, characterized in that the inflatable bag is inserted into the tubing through the tubing, and the inserted inflatable bag is inflated to close the tubing.

[0006] A method of changing the flow path of crude oil in an oil well according to the third invention includes blocking the tubing of the oil well by the method of stopping the flow of crude oil in an oil well according to the first invention or the second invention, and then providing a branch pipe connection port. , and a branch pipe attachment device capable of creating an opening by incising the wall of the tubular body without causing the fluid flowing inside the tubular body to leak to the outside. This method of changing the flow path of crude oil in an oil well is characterized in that a branch pipe of the tubing is installed on the pipe wall of the tubing and is connected to the branch pipe attachment device. In the method of changing the flow path of crude oil in an oil well according to the fourth aspect of the invention, the wall of the tubing that surrounds the tubing forming the crude oil flow path of the oil well is cut open to access the wall of the tubing. A branch pipe attachment device is provided that is provided with an opening and then a branch pipe connection port, and is capable of providing the opening by cutting the pipe wall of the pipe body without causing the fluid flowing inside the pipe body to flow outside. A method for changing the flow path of crude oil in an oil well, characterized in that a branch pipe of the tubing is attached to the pipe wall of the tubing, the branch pipe is provided via the branch pipe attachment device, and crude oil is sucked by a pump through the branch pipe. It is. In the present invention, blocking the tubing does not only mean blocking the tubing to the extent that it completely stops the flow of crude oil in the tubing, but also blocking the tubing to the extent that it stops the flow of most of the crude oil in the tubing and This includes blockages sufficient to throttle the flow of crude oil to the extent that an emergency situation can be controlled. Furthermore, in the present invention, changing the flow path does not only mean changing the flow path of crude oil to a completely different direction, but also includes changing the main flow of crude oil. The present invention will be specifically explained below.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 is a schematic sectional view showing an oil well. Normally, an oil well consists of a Christmas tree 1 on the ground, an oil extraction pipe that serves as a crude oil flow path, or tubing 2 (usually a nominal diameter of 2 to 4 inches and a depth of several thousand meters), and tubing 2 arranged concentrically on the outside. It is composed of a plurality of casings 3 arranged in a surrounding manner, and in many cases, the space between the tubing and the casings, the space between the casings, or the outside of the casing is filled or covered with cement mortar or concrete. For example, in the case of a fire in an oil well as shown in FIG. 2, a method of stopping the flow of crude oil according to the present invention will be described. First, a tunnel is built underground to reach the underground part of the burning oil well from the surface. At this time, the position where the tunnel starts to be dug, that is, the entrance of the tunnel, is determined as appropriate in consideration of safety and the like. Regarding tunnels, whether to dig a diagonal shaft, first dig a vertical shaft, and then dig a shaft parallel to the ground surface, or the depth from the ground surface,
The size of the cross section of the tunnel is determined by the site conditions, such as the strength of the ground.

When the underground casing of the oil well is reached through the excavated tunnel, the cement mortar wrapped around the outside of the casing is peeled off using a rock drill or the like to expose the casing. Next, as shown in FIG. 5(a), explosives for incision are pasted on the planned incision site of the casing.
The explosive is detonated by remote control, and the casing is cut into a predetermined area to form an opening in the casing. Needless to say, at that time, it is necessary to fully confirm that no crude oil or flammable gas has leaked into the surrounding area before detonating. If it is not possible to use explosives for safety reasons, the casing can be opened mechanically.

A specific example of cutting open the casing using explosives will be explained in more detail with reference to FIGS. 3 to 5. 3 and 4 show examples of cutting means using explosives, and the means shown in FIG.
The means shown in FIG. 3 is called ECT (Explosive Cutting Tape)7.
pe). Note that (a) in each figure
(b) shows a perspective view, and (b) shows a side view. SRT 7 in FIG. 3 and ECT in FIG. 4 are detonator 4, respectively.
It is equipped with a booster charge 5, and an explosive charge 6, and has a structure that can be attached to the casing. FIG. 5 is an explanatory view showing an example of a casing cutting operation, and FIG. 4(a) schematically shows a state before detonation in which the detonation means shown in FIG. 3 or 4 is attached to the surface to be cut, FIG. 4(b) shows a state in which an opening is opened in the tube wall of the casing after detonation. Normally, a casing is composed of a plurality of pipes arranged concentrically around the tubing, for example, pipes with nominal diameters of 30 inches, 20 inches, 13 inches, 9 inches, and 7 inches from the outside. In that case, the above operation is repeated multiple times.

[0010] Once the opening is provided in the casing, an explosive of an appropriate shape is then attached to the tubing, and the explosive is detonated by remote control to press and compress (in this case, implode) the tubing. A specific example of compressing tubing using explosives will be described in more detail with reference to FIGS. 1, 6, and 7. FIGS. 1 and 6 show an example in which the wall of the tubing is pressed and compressed almost uniformly from the radial direction toward the center of the tubing, and FIG. FIG. 2 is an explanatory diagram showing an example of a case where the wall of the tubing is compressed by pressure. In order to prevent cracks from occurring in the tubing 2 due to detonation and the consequent leakage of crude oil, the tubing 2 is preferably first covered with a cushioning material 10, such as a rubber plate. A linear detonating wire 8 is wound into a coil shape and attached on top of the buffer material layer 10 as shown in FIG. 1(a), or as shown in FIG.
) and as shown in Figure 7(a), the sheet explosives 9 are installed in a layered manner, and finally the detonator 4 is installed in the case of a detonating cord, and the booster charge 5 and the detonator 4 are installed in the case where the sheet explosive 9 is used. Attach. After confirming safety, it is detonated by remote control and the tubing is compressed by explosive force. As a result, the tubing is closed as shown in FIGS. 1(b), 6(b), and 7(b), respectively. The type and amount of explosives required for compressing the tubing are confirmed and determined in advance through experiments. This compression stops the flow of crude oil and extinguishes the fire. Even if the flow does not stop completely, oil well fires can be easily extinguished on the ground using conventional methods if the flow rate is reduced.

Even if a buffer material is used as described above, if the wall of the tubing is compressed to the extent that the diameter is significantly reduced, there is a risk that cracks may occur in the wall depending on the material of the tubing, for example. It is desirable to confirm in advance whether there is such a risk through a preliminary test. If there is a danger, the following methods can be adopted, for example. First, the diameter of the tubing is reduced by compressing the tubing using an explosive such as detonating wire 8 or sheet explosive 9 to an extent that the tubing is not damaged, thereby creating a constricted portion. Note that the diameter of the reduced portion is made smaller than the diameter of the ball 10 of the tubing cutting ball insertion device described later. Next, a leak-free tubing cutting ball insertion device shown in FIG. 8 as an example is attached to a portion of the tubing below the position of the reduced portion. FIG. 8(a) shows the state where the ball is attached to the tubing, FIG. 8(b) and FIG. 8(c) show the state in the middle, and FIG. 8(d) shows the state with the ball inserted. . Figure 8
(e) shows a state in which the ball has closed the reduced portion of the tubing.

FIG. 8(a) is a diagram showing a state in which the leak-free tubing cutting ball insertion device is attached to the wall of tubing. The tubing cutting ball insertion device is shown in Fig. 8(a).
), it is attached to surround the wall of the tubing 2. The tubing cutting ball insertion device has a contact portion 20 that comes into contact with the tube wall of the tubing 2 from two opposing directions, and the tubing cutting ball insertion device is held in the tubing 2 by surrounding the tubing 2 in cooperation with the contact portion 20. A presser plate 21, a cylinder part 22 having a hollow part in the opposite direction, and a cylinder part 22 that is driven to slide on the hollow part of the cylinder part 22, cut out a part of the pipe wall while sliding, and cut out a part of the pipe wall. A piston 11 having an opening, an explosive part 24 that propels the piston 11, a ball 12 that is held in a through hole 18 provided in the center of the piston 11 in a direction perpendicular to the piston and moves together with the piston 11; A ball-pushing gunpowder unit is provided at a position opposite to the opening in the tube wall, and applies a propulsive force from the gunpowder to the ball 12 through the through hole 18 to force the ball 12 into the tube through the opening in the tube wall. 26
It is equipped with The leak-free tubing cutting ball insertion device is formed with a fluid-tight structure, and a sealing material that can be sealed fluid-tight is interposed on the contact surface with the tube wall. An ignition powder 13 and a gunpowder 14 are installed in the gunpowder part 24 and the ball-pushing gunpowder part 26, respectively, and the piston 11 is moved by the explosive force of the gunpowder, so that the ball 12 enters the tubing 2 through the opening.

[0013] The piston 11 is equipped with a blade at a portion that contacts the tube wall of the piston, and when the ignition powder 13 in the explosive portion 24 is ignited, the piston moves due to the propulsive force of the explosive 14 and cuts a part of the tubing. An opening is made in the tube wall and the incised wall portion is pressed against the end facing the explosive part 24, and at the same time the ball 12 moves together with the piston 11 and is located above the opening in the tube wall (FIG. 8). b)). Subsequently, the ignition powder 13 in the ball-pushing gunpowder section 26 is ignited to cause the gunpowder 14 to act,
The ball 12 is pushed into the tubing 2 through the cut opening (see FIG. 8(c)). Inside the tubing 2, the crude oil is flowing upward at a certain speed, so the ball 12 is pushed upward and gets caught in the constricted part, blocking the flow path for the crude oil (Fig. 8(d)
)reference). In this case, if necessary, the apparent specific gravity of the sphere can be made lower than the specific gravity of crude oil. As described above, due to the interaction between the constricted part of the tubing and the ball, the tubing is blocked and the flow of crude oil is stopped.

Next, the second invention will be explained using a specific example. The second invention is a diagram of almost the same structure as the leak-free tubing cutting ball insertion device described above, in which the oil well casing is cut open to form an opening in the same way as the first invention, and then the tubing is compressed from the outside. In this method, an inflatable bag 16 instead of a ball is inserted into the tubing using a leak-free inflatable bag insertion device shown in No. 9, and is inflated to close the crude oil flow path of the tubing. The inflatable bag insertion device used in the present invention cuts the tube wall of the tube to provide an opening without causing the fluid flowing inside the tube to flow outside, and inserts the inflatable bag into the inflatable bag through the opening. Fire it towards the target, insert it into the tube,
It is an inflatable device. As shown in FIG. 9(a), this device has almost the same structure as the tubing cutting ball insertion device used in the first invention, and instead of the ball 12 and the ball pushing explosive part 26, an inflatable bag is used. 16, an ignition powder 13 for propelling it, and a gas generator 15 for inflating the inflatable bag body 16 are arranged at the position of the ball-pushing explosive part 26. Figure 9
As shown in (a), this leak-free inflatable bag insertion device is attached to the tubing, and as in the first invention, as shown in FIG. 9(b).
As shown in FIG. 9(c), the tube wall is cut open to form an opening, and the inflatable bag 19 is propelled by the igniter 13 and inserted into the via tubing 2 through the through hole 18 and the opening, as shown in FIG. 9(c). The inflatable bag 1 is expanded by the action of the gas generator 15 attached to this device.
6 is expanded to close the flow path within the tubing as shown in FIG. 9(d).

The method of changing the flow path of crude oil in an oil well according to the third aspect of the invention will be explained using a specific example. In the present invention, after the tubing is closed by the method according to the first and second inventions, a branch pipe is attached to the tubing below the closed part using a leak-free branch pipe attachment device. As an example of the leak-free branch pipe attachment device used in the present invention, the leak-free branch pipe attachment device shown in FIG. The ball-pushing gunpowder part 26 is not provided, and the ball-pushing gunpowder part 26 is provided instead.
The part is the branch connection port 17. As shown in FIG. 10(a), a branch pipe attachment device is attached to the tubing 2, and like the leak-free tubing cutting ball insertion device,
The piston 11 is moved with gunpowder 14, a part of the tube wall of the tubing 2 is cut open at the tip of the piston 11 to provide an opening in the tube wall, and then a branch connection port 17 is opened as shown in FIG. 10(b).
Change the crude oil flow path by connecting a branch pipe (not shown). The crude oil flows through the opening of the tubing 2 and the through hole 18 of the piston 11 of the branch pipe attachment device toward the branch pipe, changing the flow path of the crude oil in the oil well. As the branch pipe attachment device, for example, a product such as “Magic Valve” manufactured by Kitazawa Valve Co., Ltd. can be used.

Next, a method of changing the flow path of crude oil in an oil well according to the fourth aspect of the invention will be explained in detail. This method does not require occlusion of tubing. Similar to the first to third inventions, an opening is provided in the casing, and then the third invention is provided in the tubing.
After installing at least one branch pipe using a branch pipe installation device such as that used in the invention, crude oil is drawn through the branch pipe with a high capacity pump. This allows the main flow of crude oil to be diverted to the branch pipe. Here, the number of branch pipes and the suction capacity of the pump may be appropriately selected depending on, for example, the flow rate of crude oil. This method reduces the amount of crude oil leaking from the original tubing, making it easier to extinguish oil well fires, for example.

[0017]

Effects of the Invention The present invention preferably utilizes the action of gunpowder (explosives) to open the casing and compress the tubing from the outside, or inflate the inflatable bag from the inside, thereby improving the flow path of crude oil. Since this is a method of blocking the tubing, the device used is small and the operation is instantaneous, so it is possible to stop the flow of crude oil in an oil well easily, safely and reliably. Therefore, in an oil well operation emergency situation, for example in an oil well on fire, the fire can be extinguished by reliably and quickly stopping the flow of crude oil. In addition, the present invention makes it possible to quickly change the crude oil flow path easily, safely and reliably by using a leak-free branch pipe installation device that utilizes explosive power after the crude oil flow path is blocked. For example, after extinguishing an oil well that is on fire, the oil well can be regenerated in a short time.

[Brief explanation of drawings]

FIG. 1(a) is a perspective view of tubing wrapped with a detonating wire as an embodiment of the present invention before detonation;
b) is a side view showing the compressed state of the tubing after detonation when a detonating wire is used.

FIG. 2 is a schematic cross-sectional view of an oil well.

FIG. 3(a) is a perspective view of an SRT used as an example of an explosive for cutting the tube wall of a casing, and FIG. 3(b) is a side view thereof.

FIG. 4(a) is a perspective view of an ECT used as another example of an explosive for cutting the tube wall of a casing, and FIG. 4(b) is a side view thereof.

FIG. 5(a) shows the state of the casing loaded with explosives before detonation, and FIG. 5(b) shows the opening provided in the casing after detonation.

FIG. 6(a) is an explanatory diagram showing a specific example before detonation when tubing is uniformly compressed in the radial direction using a sheet explosive, and FIG. 6(b) shows the state after detonation.

FIG. 7(a) is an explanatory diagram showing a specific example before detonation when tubing is compressed from two opposing directions using sheet explosives, and (b) is a side view of the tubing after detonation. (c) is a cross-sectional view of the tubing after detonation as seen from line A-A in (b).

FIG. 8 is an explanatory diagram showing an example of a tubing cutting ball insertion device, in which (a) shows a state where it is attached to tubing, (b) and (c) show a state in the middle, and (d) shows a state in the middle. , shows the state in which the sphere is inserted. (e) is a cross-sectional view taken along line A--I in (d) showing a state in which the reduced portion of the tubing is closed by the ball.

FIG. 9 is an explanatory diagram showing an example of an expandable body insertion device;
(a) shows the state attached to the tubing, (b)
and (c) show the state in the middle, and (d) shows the state where the expanded inflatable bag has closed the tubing.

FIG. 10 is an explanatory diagram showing an example of a branch pipe installation device;
(a) shows the situation before operation, and (b) shows the situation after operation.

[Explanation of symbols]

1. Christmas tree 2 Tubing 3 Casing 4 Detonator 5 Booster medicine 6 Explosives 7 SRT 8 Detonating wire 9 Sheet explosives 10 Cushioning material 11 Piston 12 Ball 13 Ignition powder 14 Gunpowder 15 Gas generator 16 Inflatable bag body 17 Branch pipe connection port 18 Through hole 20 Contact part 21 Holding plate 22 Cylinder part 24 Gunpowder Department 26 Ball closet gunpowder section

Claims (4)

[Claims] Claim 1: A wall of a casing that surrounds a tubing that forms a crude oil flow path in an oil well is cut open to provide an opening that allows access to the wall of the tubing, and then the wall of the tubing is opened. A method for stopping the flow of crude oil in an oil well, characterized in that the diameter of the tubing is reduced by pressing it toward the center of the tubing, thereby closing the tubing. 2. A wall of a casing that surrounds the tubing that forms a crude oil flow path in an oil well is cut open to provide an opening that allows access to the wall of the tubing, and then the inside of the tubing is opened. An inflatable bag in which an opening is provided by cutting the tube wall of the tube body without causing the flowing fluid to leak to the outside, and an inflatable bag body is inserted into the tube body through the opening and inflated. attaching a bag insertion device to the tube wall of the tubing, providing an opening in the tube wall of the tubing with the inflatable bag insertion device, and inserting the inflatable bag into the tubing through the opening; A method for stopping the flow of crude oil in an oil well, comprising inflating the inserted inflatable bag to close the tubing. 3. After the tubing of the oil well is closed by the method of stopping the flow of crude oil in the oil well according to claim 1 or 2, the tubing is provided with a branch pipe connection port and the fluid flowing inside the pipe body is discharged to the outside. A branch pipe attachment device that can cut open the tube wall of the tubular body to create an opening without causing any outflow is attached to the tube wall of the tubing below the blocked portion of the tubing, and the branch tube attachment device is inserted through the branch tube attachment device. A method for changing the flow path of crude oil in an oil well, characterized by providing a branch pipe of the tubing. 4. The wall of the casing that surrounds the tubing that forms the crude oil flow path of the oil well is cut open to provide an opening that allows access to the wall of the tubing, and then a branch pipe connection port is provided. A branch pipe attachment device is attached to the pipe wall of the tubing, and is capable of cutting the pipe wall of the pipe body to provide an opening without causing the fluid flowing inside the pipe body to leak to the outside. A method for changing the flow path of crude oil in an oil well, characterized in that a branch pipe of the tubing is provided via a pipe fitting device, and crude oil is sucked by a pump through the branch pipe.